Canavan Disease (ASPA)
Canavan disease is an autosomal recessive disorder caused by pathogenic variants in the gene ASPA and is most commonly observed among those of Ashkenazi Jewish descent and European ancestry. The neonatal/infantile form of Canavan disease is severe and characterized by enlarged head circumference, developmental delay, hypotonia, and failure to thrive. The progression of the disease leads to severe muscle weakness and inability to sit without support and to eat independently. Life expectancy is usually shortened to mid-teen years. The milder form of Canavan disease is characterized by mild developmental delays that may be unrecognized throughout life. Several specific variants have been associated with the infantile and later-onset forms of the disease, and therefore the severity of the disease may be predicted based on the genotype in some patients. Individuals with one mild variant and one severe variant usually present with the milder form of Canavan disease.
For information about carrier frequency and residual risk, please see the residual risk table.